TABLE OF CONTENTS During construction, partially completed masonry work requires some protection from damage caused by weather or by other construction operations.
High-lift grouting requires that walls be temporarily braced until the mortar and grout has fully set. Partially completed walls should also be braced during construction against lateral loads from wind or other forces applied before full design strength is attained or before permanent supporting construction is completed (Figure 5-32). Partially completed structures may be subject to loads which exceed their structural capabilities. Wind pressure, for instance, can create four times as much bending stress in a new, freestanding wall as in the wall of a completed building. Fresh masonry with uncured mortar has no tensile strength to resist such lateral forces. Most codes require that new, uncured, unanchored walls be braced against wind pressure. Bracing should be provided until the mortar has cured and the wall has been integrally tied to the structural frame of the building. Bracing should be designed on the basis of wall height and expected wind pressures.
Masonry walls should be covered at the end of each day and when work is not in progress. Excess moisture entering the wall during construction can cause saturation of units, which may take weeks or months to dry out. Such prolonged wetting may result in efflorescence, particularly if the cooler winter months lengthen the drying process. Extended wetting will also prolong cement hydration, producing large amounts of calcium hydroxide, which may also be...
